Crane.



A. WELIN.

CRANE.

APPLICATION FILED JULY 26.1915.

Patented May 21,1918.

AXEL WELIN, OF LONDON, ENGLAND.

CRANE.

Specification of Letters Patent.

Patented May 21, 1918.

Application filed July 26, 1915. Serial No. 41,904.

To (115 whom it may concern:

Be it known that I, AXEL VVELIN, a subject of the King of Sweden, residing at Hopetoun House, Lloyds avenue, in the city of London, England, have invented new and useful Improvements in Cranes, of which the following is a specification.

This invention relates to cranes of the type in which the crane arm or jib is capable of being luffed about a horizontal axis and its object is to provide improved means for compensating, that is, for arranging that the path of the load may approximate to the horizontal despite the fact that the jib head is lowered as it is lufi'ed out.

My invention is illustrated by the accompanying drawing which is a side elevation of a crane such as is employed as a davit for lowering boats.

a is a frame in which is mounted a horizontal pin Z) fast with which is a jib c. On the jib is a curved rack d meshing with a pinion e fast with a worm wheel f which is mounted in the frame and can be turned by means of a crank handle 9. At the head of the jib is mounted a guide or sheave 71, over which passes a rope '11 from the end of which is suspended the usual block j. The rope is led backward from the head of the jib and its other end is secured to the rack d. On the top of the frame are ournaled two pulleys 70 Z in such a position that as the jib is lufi'ed downward in either direction from its vertical position, the rope i is caught by one of these pulleys and pulled in thus causing the block j to rise through approximately the same distance as the head of the jib falls. Similarly, when the jib is lufl'ed in the rope is paid out and in consequence the path of the load during luffing is approximately horizontal.

What I claim is In combination, a crane arm capable of being lui'fed about a horizontal pivot and having a guide at its head, a frame comprising a vertical column mounted contiguous to said pivot, actuating mechanism mounted in said frame intermediate its ends, a connecting member connected to said davit at one end and movable inwardly and outwardly by said actuating mechanism, twin pulleys mounted at the head of said frame in oontiguity to each other and having peripheral grooves in the same plane so located as to form a rope-channel, a rope passing over the guide at the head of the crane, through said rope-channel and connected to said movable connecting member intermediate its ends, whereby said rope is caused to swing from one pulley to the other and to bend in opposite directions to provide evenly adjusted compensating pulls on said rope in two directions during the movement of said connecting member in one direction.

AXEL WELIN.

- 90p! of this patent may be obtained for five cents each, by addressing the Commissioner of Patentfl,

Washington, D. 0." 

